In fig, QTPR=QRQS and ∠1=∠2. Prove that △PQS∼△TQR.
∠1=∠2(Given)
⇒ PR = PQ ...(i)
(Sides opposite to equal angles in △QRP)
Also QTPR=QRQS (Given) ...(ii)
From (i) and (ii), we have
QTPR=QRQS⇒QPQT=QSQR ...(iii)
Now, in triangle PQR and TQR (each=∠1)
and PQTQ=QSQR(from(3))
⇒△PQS∼△TQR(SASSimilarity)